Cervix dilation or cervical dilation is the widening of the mouth of the cervix during spontaneous or induced labor. This is a gradual process and the mouth becomes wider as labor progresses towards childbirth. Cervical dilation is a product of another process occurring in the cervix called Effacement.

As due date approaches, the mother’s uterus starts preparing for the upcoming process of labor and one of the preparations is to thin out the cervix and “pull it up”. As effacement becomes complete, the cervix virtually blends with the lower part of the uterus.

Effacement starts causing a gap between the lips of the cervix and causes the gap to slowly widen resulting in progressive dilation.

The natural cause of cervical dilation is preparation of labor and the actual process. This is to ensure smooth, uninterrupted movement of the baby out of the uterus through the birth canal.

Symptoms Of Cervix Dilation In Pregnancy

A thick plug of mucus can suddenly loosen out and discharge through the vagina. This is the mucus which was, until now, blocking the entrance of the cervix and preventing infection. The discharge of mucus indicates that the cervix has begun dilating.

The mucus plug can also be tinged with blood making it pinkish in color. This is absolutely normal, and the mucus plug with blood is called “show”.

As the cervix begins dilating, pain in the lower abdomen and back begins, which is very similar to but more severe than pains of menstruation.

How To Check Cervical Dilation?

Usually, a doctor or midwife checks for the width of cervical dilation that has occurred. However, a self-exam can also be done albeit carefully. You can do this check by lying on your bed propped up by pillows.

Make sure that your fingers are absolutely clean because there is a risk of infection. It would be safer to wear sterile gloves.

Two well-lubricated fingers are then gently introduced into the vagina. If you feel an opening in the cervix, it means that dilation has begun. For every one finger you are able to insert in the cervical opening, it approximately means that your cervix has dilated by one centimeter.

You may also be able to feel the amniotic membranes just inside the cervical opening. If you feel only the baby’s head, it means that the membranes have ruptured.

Stages Of Dilation Of Cervix

Cervical dilation is a reliable aid to know the progression of labor. The cervix is generally said to dilate by 1 centimeter during every hour of labor. However, it is not a universal rule in all pregnancies because it has been seen that certain amount of cervical dilation takes place even before the onset of labor pains.

A dilation of 0 to 4 centimeters is considered to be seen in early stages of labor.

When the stage of active labor comes on, the cervix gets dilated anywhere between 4 to 7 centimeters.

Next comes the stage of transition, which is the bridging level between labor and delivery. Here, cervical dilation occurs between 7 to 10 centimeters.

The cervix is finally considered to be fully dilated when its mouth is 10 centimeters wide and the baby’s head can come through.